This section introduces aspects that may help facilitate a better understanding of the disclosure. Accordingly, these statements are to be read in this light and are not to be understood as admissions about what is or is not prior art.
The demand for faster devices operating in ps or fs regimes is now here corresponding with Moore's law. Consequently, at these speeds the need for lower energy devices is critical. Thus, spintronics is now becoming a choice technology for a variety of different applications including memory and logic. The magnetic tunnel junction is now the most ubiquitous spintronic memory device in which the magnetization of the storage layer is switched by spin-transfer-torque or spin-orbit torque interactions. Whereas these novel spin-torque interactions exemplify the potential of electron-spin-based devices and memory, the switching speed is limited to the ns regime because of the precessional motion of the magnetization. In particular, state of the art spin-transfer-torque magnetic tunnel junctions (STT-MTJ) require high current densities of the order of 107-108 A/cm2, making them unattractive from an energy consumption perspective for high frequency applications of ps or fs magnetization switching. In addition such high current densities can result in electrical breakdown of the MgO tunnel barrier, negatively impacting their reliability.
An all-optical magnetization switching, largely based on the inverse Faraday effect, has been shown to be an attractive method for achieving magnetization switching at ps speeds. While these devices have been shown to operate at the desired switching speeds, they are not compatible with semiconductor manufacturing processing.
Therefore, there is an unmet need for a novel optical switching mechanism that can work with semiconductor-based ultra-high density integrated nanostructure fabrication.